Aquarium



FIG. 1 is an isometric view taken from the top, front and left side of an aquarium showing my new design;

FIG. 2 is an isometric view taken from the bottom, rear and right side thereof; and

FIG. 3 is a bottom plan view thereof.

The broken line representation of gravel in FIG. 1 is for purposes of illustration only. 

The ornamental design for an aquarium, as shown and described. 